entries → 唇
TSUMUGU · TOCFL C1 (est.) · 字
唇 character · TOCFL C1 (est.)
唇 ＝ 口 ＋ 辰
ㄔㄨㄣˊ · chún
noun — lip

字源 FORM — what the parts do

口義the mouth
辰聲chén — gives the sounda clam shell, the old planting-season sign
Tchén → chún — same chun, the tone rises
The mouth (口) and its edge of flesh — the lip. 辰 chén carries the sound, the tone lifting to chún. The graph also writes the older 脣, which marks the flesh with 肉 instead.
意 · Meanings
(本義)嘴唇— lip常用
→唇齒、唇亡齒寒— lips and teeth — closely bound
(本義) original meaning · → ⇒ each arrow = one more step of extension
關 · Related
脣＝ 肉 ＋ 辰chúnthe older twin — 脣 marks the flesh 肉, 唇 sets the mouth 口 below 辰辰chénthe sound donor — the clam shell, the planting season